Rod scalping machine



Oct. 11, 1966 H. LINDEMANN 3,277,752

ROD SCALPING MACHINE Filed June 16, 1964 5 Sheets-Sheet 1 Maw: /AwAM/a/v/v BY Mow (2M7) FIG. 7

Oct. 11, 1966 H. LINDEMANN ROD SCALPING MACHINE 5 Sheets-Sheet 5 Filed June 16, 1964 NM e 58 0 m m 2 m Mm yr m fi i a a K S 7 S W 1 m h? a fir a? N N 1' 7. 1 V .1 1%: II M Q a g a s l w a b\ Q ON g m w 0, m M Q M 9m United States Patent 3,277,752 ROD SCALPING MACHINE Hans Lindemann, Linderstrasse 39, Grossdornberg, near Bielefeld, Germany Filed June 16, 1964, Ser. No. 375,433 Claims priority, application Germany, June 25, 1963, L 45,194; Apr. 24, 1964, L 47,689, L 47,690 11 Claims. (Cl. 82-20) The present invention relates to improvements in a rod scalping machine of the known type in which the rod stock which is secured against rotation is fed in its axial direction through a revolving cutter head and is guided directly in front and at the rear of the cutter head by nonrotating radially resilient guide means so that the intermediate part of the rod which is being scalped is disposed exactly coaxially to the cutter head. These rear guide means are mounted at the inside of and are thus surrounded by at least one of the bearings on which the cutter head is supported.

A scalping machine of the above-mentioned type permits rod-shaped materials to be cut to certain diameters at a degree of accuracy which depends primarily upon the tolerances of the hearings on which the revolving cutter head is mounted. The cutter head itself is secured to a tubular shaft at the inside of which the bearings are mounted which, in turn, are mounted on a stationary sleeve which is secured to the machine frame and at the inside of which the rear guide means are mounted in a position closely adjacent to the cutter head. These rear bearings which support the revolving cutter head on the stationary sleeve must necessarily be of a relatively large diameter. Since large bearings are, however, bound to have a larger bearing clearance than small ones, this means that, even though the guide means are capable of damping all vibrations of the part of the rod which is disposed between the guide means in front of and behind the cutter head, it is not possible to scalp the rod-shaped material to a diameter as accurately as may be desired.

It is therefore the principal object of the present invention to provide a rod scalping machine with suitable means which will overcome the above-mentioned disadvantage and also permit rod stock and the like of a relatively large diameter to be scalped so that the desired final diameter of such stock will be reached at a higher degree of accuracy than it was possible prior to this invention.

For attaining this object, the present invention provides at least one additional bearing of the smallest possible diameter and a very small bearing clearance for supporting the cutter head at a point located between the cutter head and at least one of the nonrotating guide means. One race of this hearing is secured by a flange or the like to the cutter head itself, while the other race is secured to a nonrotating part, for example, the head of the guide means which are located directly adjacent to this bearing. The race with the smallest diameter is then preferably secured to the cutter head and that with the largest diameter to the nonrotating part.

In addition, suitable spring means may be provided which tend to press the head of the guide means in front of the cutter head in the direction toward the latter so that the two races of the small bearing will be under a lateral pressure relative to each other and thereby re duce the small tolerance which this bearing might have to the utmost extent.

The small additional bearing for supporting the cutter head with the smallest possible bearing clearance or tolerance may therefore be mounted either between the guide means which are located in front of the cutter head and the cutter head itself or between the latter and the guide means which are located directly behind the cutter 3,277,752 Patented Oct. 11, 1966 head. It is also possible according to the invention to provide two of these small bearings, one between the front guide means and the cutter head and the other between the cutter head and the rear guide means. If only one of these additional bearings is provided between the front guide means and the cutter head, the cutter head should be directly connected to its tubular drive shaft. The same may also apply if there is only one small bearing provided between the cutter head and the rear guide means. In the latter case, and especially if two such small bearings are provided in front of and behind the cutter head, it is, however, more advisable to connect the cutter head indirectly to its tubular drive shaft by means of a resilient element.

In the event that the rod stock should not only be scalped very accurately to a certain diameter, but the cutting diameter of the scalping blades in the cutter head should also be adjustable so as to attain a rod or shaft of a different diameter or to provide it with one or more parts of a larger or smaller diameter, the invention further provides that, instead of connecting one race of the small front bearing directly to the cutter head by means of a flange, this flange be provided with an annular projection which engages into the central bore of the cutter head and has a conical surface upon which the scalping blades engage, and that suitable means are provided for shifting the other race which is connected to the nonrotating part in the axial direction so that thereby the entire front bearing is shifted and the conical projection is inserted more or less deeply into the bore of the cutter head and against the correspondingly inclined end surfaces of the scalping blades which may thus be adjusted to different scalping diameters. In order to prevent any relative rotation between the conical projection and the cutter head, it is advisable to connect them by suitable guide means which permit the projection to slide in the axial direction relative to the cutter head but lock these parts together in the rotary direction.

The various features and advantages of the present invention will become more clearly apparent from the following detailed description thereof which is to be read with reference to the accompanying drawings, in which FIGURE 1 shows a longitudinal section of the principal parts of a scalping machine according to the invention which is provided with a bearing of a relatively small diameter between the cutter head and the guide means which are located in front of the cutter head;

FIGURE 2 shows a longitudinal section similar to that according to FIGURE 1 of a modification of the scalping machine in which a bearing of a relatively small diameter is mounted between the cutter head and the guide means which are located behind the cutter head; while FIGURE 3 shows a similar longitudinal section of a further modification of the scalping machine in which the rflange which supports the inner race of the small bearing is mounted in a bore in the cutter head in order to permit the scalping diameter of the cutting blades to be varied by an axial adjustment of the bearing.

rReferring first to FIGURE 1 of the drawings, the rod stock 1 to be scalped is secured against rotation and fed through the scalping machine in the direction of the arrow 2. During this movement, the outer surface of the rod stock is cut or scalped by the scalping blades 4 which are mounted in the revolving cutter head 3. This cutter head 3 is secured to the end of a tubular drive shaft 5 which is rotatably mounted by means of bearings :6 on a stationary sleeve-7 which is rigidly secured to the bench or frame 8 of the machine. Drive shaft 5 has an outer gear rim 9 for being driven by a chain or a turbine. Directly in front and at the rear of the cutter head 3 the machine is provided with nonrotating guide means which are of a conventional type and are therefore indicated merely diagrammatically and which comprise front and rear guide jaws 11 and 13 which are in resilient engagement with the rod 1 and prevent any vibrations of the part of the latter which is disposed between these guide jaws and is being worked upon by the scalping blades 4 which are mounted in the cutter head 3. In place of such guide jaws it is also possible to employ guide rollers which engage resiliently with the rod to be scalped but only act as sliding guides. The front guide jaws 11 are mounted in a supporting head which is covered by a plate 19 and mounted by a flange or other connecting element 12 on the bench or frame 8 of the machine. The rear guide jaws 13 which likewise engage resiliently with the rod 1 are mounted at the inside of the end of a tubular member 27 which is inserted into the stationary sleeve 7 and locked thereto or to another stationary element of the machine.

According to the present invention, the cutter head 3 according to FIGURE 1 is supported by an additional bearing 14 which is located between the guide means 10, 11 in front of the cutter head 3 and the cutter head itself and has the smallest possible diameter and the smallest possible bearing clearance. The inner race 15 of this bearing is mounted on a flange 16 which is secured to the cutter head 3, while the outer race 17 is mounted in a {huge 18 which is secured to the end plate 19 on the supporting head 10.

\Numerous tests have shown that, even though the small supporting bearing 14 was one of a conventional type, the ovalization of a scalped rod 1 of a diameter of, for example, 100 mm. amounted to less than 1/100 mm. Since during the scalping operation the connecting element 12 was additionally pressed in the direction of the arrow 2 by the action of a spring, not shown in FIGURE 1, not only any possible bearing clearance of the small bearing 14, but also the bearing clearance of the large bearings 6 was eliminated. By the addition of such a small supporting bearing 14, the scalping machine is therefore capable of scalping rod stock at a degree of accuracy which is otherwise attainable only by means of a precision grinding machine.

In the scalping machine according to the modification of the invention as illustrated in FIGURE 2, the small supporting bearing 14 is mounted between the cutter head 3 and the rear guide means 13. The cutter head 3 is in this case connected to the tubular drive shaft by means of a resilient connecting element 26. The inner race of bearing 14 is again mounted on a flange 16 which is secured to the cutter head 3, while the outer race of this hearing is mounted within a flange 18 which is secured to the sleeve 7 and/or to the tubular member 27 which carries the guide means 13.

If desired, the scalping machine according to FIGURE 2 may be equipped with a second supporting bearing which may be mounted in the same manner as shown in FIGURE 1, that is, in the space in FIGURE 2 between the cutter head 3 and the front guide means 11, 12. The inner race of this second hearing may therefore also be mounted on a flange 16 which is secured to the cutter head 3, and its outer race within a flange 18 which is secured to the plate 19. If such a second bearing 14 is omitted, the connecting element 12 should be moved more closely toward the cutter head 3 and then be locked in a fixed position. This connecting element 12 should therefore be movable in the axial direction, as indicated in FIGURE 2 by the double-arrow 28, which also permits the cutter head 3 to be easily exchanged.

FIGURE 3 shows another modification of the invention in which the small supporting bearing 14 is again mounted in front of the cutter head 3. Flange 16 on which the inner race 15 of bearing 14 is mounted is, however, in this case provided with an annular extension 20 which is slida-ble along the wall of the bore 21 in the cutter head 3 and provided on its inner side with a conical surface 22 which engages with the corresponding inclined surfaces of the scalping blades 4. If the connecting element 12 is shifted in the axial direction, for example, by a lever 24 which is pivotably mounted at 23 or by any other suitable means, the cutting diameter of the scalping blades 4 may be varied. Flange 16 with its extension 20 in the bore 21 is preferably locked against rotation by a tongue-and-groove connection 25 or the like. Of course, the connecting element 12 should be guided so as to be movable merely in the axial direction and should be adapted to be locked in any position to which it may be adjusted.

Although my invention has been illustrated and described with reference to the preferred embodiments thereof, I wish to have it understood that it is in no way limited to the details of such embodiments, but is capable of numerous modifications within the scope of the appended claims.

Having thus fully disclosed my invention, What I claim 1. A rod scalping machine comprising a stationary frame, a tubular member rigidly secured to said frame, bearing means mounted on the outer peripheral surface of said tubular member, a tubular drive shaft surrounding said tubular member, and rotatably mounted on said bearing means, a rotary cutter head secured to one end of said drive shaft coaxially thereto and adapted to be driven thereby and having a central aperture, cutting blades mounted on said cutter head and projecting into said aperture, radially resilient but nonrotatable guide means located in front and at the rear of said rotary cutter head and at small distances therefrom and adapted to guide a nonrotatable rod coaxially with said cutter head when said rod is fed in its axial direction through said front guide means, between said cutting blades on said rotary cutter head so as to be scalped thereby, and through said rear guide means in said tubular member, normally stationary guide supporting means for holding said front guide means, said tubular member containing and form ing the supporting means of said rear guide means, and at least one antifriction bearing surrounding said rod at a small radial distance therefrom and interposed between said cutter head and at least one of said guide means, said last bearing having inner and outer races with inner and outer diameters considerably smaller than those of said first bearings and also having a very small bearing clearance, means for securing one of said races to the supporting means of one of said nonrotatable guide means and closely adjacent to said last guide means, and means for securing the other race to said rotary cutter head and closely adjacent thereto.

2. A rod scalping machine as defined in claim 1, whereing said inner race of said small bearing is secured to said rotary cutter head and said outer race to said supporting means of said guide means directly adjacent thereto.

3. A rod scalping machine as defined in claim 1, wherein said small bearing is located between said front guide means and said cutter head.

4. A rod scalping machine as defined in claim 1, wherein said small bearing is located between said cutter head and said rear guide means.

5. A rod scalping machine as defined in claim 4, further comprising at least one resilient element interposed between and secured to said cutter head and said tubular drive shaft for resiliently connecting said cutter head to said drive shaft.

6. A rod scalping machine as defined in claim 1, wherein a pair of said small bearings is located at both sides of said cutter head and closely adjacent thereto.

7. A rod scalping machine as defined in claim 6, wherein the inner races of said small bearings are secured to Sa d cutter head and the outer race of each of them is secured to the supporting means of said guide means directly adjacent thereto.

8. A rod scalping machine as defined in claim 1, wherein said securing means for said races comprise a pair of annular flanges secured to the supporting means of one of said guide means and to said cutter head, respectively, said inner race being secured to the outer surface of said flange on said cutter head, and said outer race being secured to the inner surface of said flange on said guide supporting means.

9. A rod scalping machine as defined in claim 3, further comprising spring means acting upon said supporting means of said front guide means and tending to press the same at least during the scalping operation in the direction toward said cutter head.

10. A rod scalping machine as defined in claim 3, Wherein said securing means for one of said races comprise an annular flange rigidly secured to said supporting means of said front guide means, said securing means for the other race comprising an annular adjusting flange axially projecting from said other race into said aperture of said cutter head and having an outer surface axially slidable along the Wall of said aperture and an inner conical surface engaging upon the outer ends of said cutting blades, and means for shifting said supporting means of said front guide means in the axial direction, whereby said cutting blades may be adjusted in substantially radial directions to vary the scalping diameter thereof.

11. A rod scalping machine as defined in claim 10, further comprising means for preventing any relative rotation between said adjusting flange and said cutter head.

References Cited by the Examiner UNITED STATES PATENTS 3,038,361 6/1962 Holzer 82-20 X WILLIAM W. DYER, JR., Primary Examiner. LEONIDAS VLACHOS, Examiner. 

1. A ROD SCALPING MACHINE COMPRISING A STATIONARY FRAME, A TUBULAR MEMBER RIGIDLY SECURED TO SAID FRAME, BEARING MEANS MOUNTED ON THE OUTER PERIPHERAL SURFACE OF SAID TUBULAR MEMBER, A TUBULAR DRIVE SHAFT SURROUNDING SAID TUBULAR MEMBER, AND ROTATABLY MOUNTED ON SAID BEARING MEANS, A ROTARY CUTTER HEAD SECURED TO ONE END OF SAID DRIVE SHAFT COAXIALLY THERETO AND ADAPTED TO BE DRIVEN THEREBY AND HAVING A CENTRAL APERTURE, CUTTING BLADES MOUNTED ON SAID CUTTER HEAD AND PROJECTING INTO SAID APERTURE, RADIALLY RESILIENT BUT NONROTATABLE GUIDE MEANS LOCATED IN FRONT AND AT THE REAR OF SAID ROTARY CUTTER HEAD AND AT SMALL DISTANCES THEREFROM AND ADAPTED TO GUIDE A NONROTATABLE ROD COAXIALLY WITH SAID CUTTER HEAD WHEN SAID ROD IS FED IN ITS AXIAL DIRECTION THROUGH SAID FRONT GUID MEANS, BETWEEN SAID CUTTING BLADES ON SAID ROTARY CUTTER HEAD SO AS TO BE SCALPED THEREBY, AND THROUGH SAID REAR GUIDE MEANS IN SAID TUBULAR MEMBER, NORMALLY STATIONARY GUID SUPPORTING MEANS FOR HOLDING SAID FRONT GUIDE MEANS, SAID TUBULAR MEMBER CONTAINING AND FORMING THE SUPPORTING MEANS OF SAID GEAR GUIDE MEANS, AND AT LEAST ONE ANTIFRICTION BEARING SURROUNDING SAID ROD AT A SMALL RADIAL DISTANCE THEREFROM AND INTERPSED BETWEEN SAID CUTTER HEAD AND AT LEAST ONE OF SAID GUIDE MEANS, SAID LAST BEARING HAVING INNER AND OUTER RACES WITH INNER AND OUTER DIAMETERS CONSIDERABLY SMALLER THAN THOSE OF SAID FIRST BEARINGS AND ALSO HAVING A VERY SMALL BEARING CLEARANCE, MEANS FOR SECURING ONE OF SAID RACES TO THE SUPPORTING MEANS OF ONE OF SAID NONROTATABLE GUIDE MEANS AND CLOSELY ADJACENT TO SAID LAST GUIDE MEANS, AND MEANS FOR SECURING THE OTHER RACE TO SAID ROTARY CUTTER HEAD AND CLOSELY ADJACENT THERETO. 